If water is flowing out the bottom of the container, that’s too much water鈥攁t least for nasturtiums. See above; overwatering is ill advised. That may be the cause of the yellow leaves, or it could be a pest bug; nasturtiums are notorious aphid magnets. See above and click through. The 鈥渓ong roots鈥 are harder to explain. Moving on, it is said that nasturtiums do not transplant well, so moving to a larger container may not be successful. If the long-term plan was to transplant them, starting seeds in peat pots is recommended because the entire pot would be planted, leaving the roots undisturbed. Depending on how the plant is doing in the near term, it may be worth your while to start again, if possible鈥攊t’s still early in the growing season! Read the guidance above and see if you get better results.
If water is flowing out the bottom of the container, that’s too much water鈥攁t least for nasturtiums. See above; overwatering is ill advised. That may be the cause of the yellow leaves, or it could be a pest bug; nasturtiums are notorious aphid magnets. See above and click through. The 鈥渓ong roots鈥 are harder to explain. Moving on, it is said that nasturtiums do not transplant well, so moving to a larger container may not be successful. If the long-term plan was to transplant them, starting seeds in peat pots is recommended because the entire pot would be planted, leaving the roots undisturbed. Depending on how the plant is doing in the near term, it may be worth your while to start again, if possible鈥攊t’s still early in the growing season! Read the guidance above and see if you get better results.